Yan-Hong Huang and Xiang-Kun Wang
Agronomy Dept.. Beijing Agric. University, Beijing. 100094 China
frequency of gene i at locus j and n is the number
of loci examined. The values obtained for the three sites are given in
Table 1. Fusui population had the highest gene diversity and Dongxiang
population the lowest. Possibly, the high diversity of Fusui population
is attributable to introgression of genes from cultivated rice.
The Indica (or Hsien, H) and Japonica (or Keng,
K) types have different alleles at each of the seven isozyme loci, and
accordingly show different allelic constitutions as shown in Table 2. Many
plants examined had a combination of the alleles from typical Indica and
Japonica parents. Those having more than four (4, 5 and 6) Japonica-type
Table 1. Average gene diversity (H) estimated in three populations
of wild rice
Population | No. of strains observed | H |
Dongxiang, Jiangxi | 41 | 0.110 |
Guilin, Guangxi | 21 | 0.136 |
Fusui, Guangxi | 30 | 0.157 |
Table 2. Allelic constitution for seven isozyme loci detected in common
wild-rice strains of three populations
Code | Type
classified |
Est-3 |
Alleles observed at:
Cat-1 Amp-2 |
Acp-I |
Acp-2 |
Mal-1 |
Mal-2 |
No. of strains |
1 | K | 1 | 2 4 | 2 | 0 | 2 | 1 | 1 |
2 | K | 1 | 2 1 | 2 | 0 | 2 | 1 | 4 |
3 | K' | 1 | 2 1 | 1 | 1 | 2 | 2 | 44 |
4 | K' | 1 | 2 1 | 1 | 0 | 2 | 2 | 2 |
5 | K- | 1 | 2 1 | 2 | 0 | 2 | 2 | 12 |
6 | K' | 1 | 1 1 | 2 | 0 | 2 | 2 | 1 |
7 | K' | 1 | 2 1 | 1 | 1 | 2 | 1 | 9 |
8 | K' | 1 | 2 1 | 1 | 0 | 2 | 1 | 4 |
9 | K' | 1 | 2 2 | 2 | 0 | 2 | 2 | 1 |
10 | K' | 1 | 2 4 | 2 | 0 | 1 | 2 | 1 |
11 | H' | 1 | 1 1 | 1 | 1 | 1 | 2 | 6 |
12 | H' | 2 | 1 1 | 1 | 1 | 1 | 2 | 2 |
13 | H' | 2 | 2 1 | 1 | 1 | 1 | 2 | 4 |
14 | H' | 1 | 2 2 | 1 | 1 | 1 | 2 | 1 |
15 | H | 1 | 1 2 | 1 | 1 | 1 | 1 | 0/92 |
alleles were taken as Japonica-cline (K') and more than four Indica-type alleles as Indica-cline (H'). Then. the wild-rice strains examined. 92 in total, were classified into 5K. 74K' and 13H' types: there was no true H types (Table 2).
The frequencies of K, K' and H' types among strains from the three sites are given in Table 3. The plants from Dongxiang were mostly of K' type. although K' was generally dominant at all sites. In the light of this observation, the Chinese common wild rice may be considered to have a potentiality of Indica-Japonica differentiation, even though the plants are not differentiated yet.
Table 3. Number of strains classified as K, K' and H' types in three
populations
Population | K | K' | H' |
Dongxiang, Jiangxi | 40 | 1 | |
Guilin, Guangxi | 5 | 16 | |
Fusui, Guangxi | 18 | 12 |
K: having Japonica alleles at all 7 loci
K': having Japonica alleles at 4, 5 or 6 loci
H': having Indica alleles at 4.5 or 6 loci
References
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